You forgot a couple
1. M5, from a famous Star Trek OS episode whose title I've somehow forgotten. Nothing surprising about the plot -- your basic "computer develops awareness, gets megalomania, tries to take over ship" kind of plot -- but quite well done, with a plot twist in which, when its designer explains that what it's done is horribly wrong, the computer chooses suicide.
2. The computer in THX 1138 -- or, as I call it, The Only George Lucas Film That Matters -- while not a "character" per se, is still a hugely influential part of the plot. The closest it comes to being an actual character in the film is when it appears as the wise, bearded face on the big screen in the digitally-networked confessional booths throughout the underground city where THX lives.